Empty OPML, can't import 

The XML file looks valid, but my podcast manager doesn't import it.

I also see an OPML file but it appears empty:

```
<?xml version="1.0" encoding="UTF-8"?>
<opml version="1.0">
	<head>
		<title>Podsync feeds</title>
	</head>
	<body></body>
</opml>
```

Am I missing something obvious? 